GPS (Global Positioning System) devices are everywhere. These devices provide a user with such information as latitude and longitude, accurate time, heading, velocity, etc. GPS devices are particularly useful in automobiles and other vehicles. Many individuals have multiple GPS devices if they own, for instance, two cars that both have the device. Conventionally, most devices will allow a user to store information such as address points in the internal memory of the device. Some devices will allow you to store this information on removable memory, e.g., memory cards, optical media, etc. In the latter case, this can be particularly helpful because a list of addresses, for instance, will be useful to be moved from GPS device (e.g., a first vehicle) to GPS device (e.g., a second vehicle).
Conventionally, a GPS device will inform a user how to get from one point to another. Additionally, it provides information on points of interest, e.g., hotels, restaurants, historic landmarks, etc. Some GPS units will also provide information including current speed of travel as well as average speed of travel.
As a driver moves his vehicle (e.g., boat or car), speed limits change quite rapidly. It is quite common for a driver to be unaware that he was violating the speed limit. That claim is made every day as drivers are ticketed. Radar detectors, which are quite common, only tell the driver if a law enforcement person is in the area and trying to catch speeders. Either these detectors do not work, or they work too late to avoid law enforcement problems. They also are difficult to place in a vehicle and many law enforcement agencies frown on these devices; in fact, radar detectors are illegal in some states. Of course, in all cases, radar detectors do not let the user know the speed that he is traveling. Thus, a need exists for techniques of alerting a driver as to the speed limit of any road traveled, and if they are violating or obeying that speed limit.
In another related area, a need also exists to inform an outside selected source as to what speed various vehicles are driving on a particular road way or waterway. If, for instance, the speed limit of a road is 65 miles per hour (e.g., on a highway) and an individual or computer detected that several vehicles in the same location were traveling at 10 miles per hour (during a certain time period) then that information source could report a traffic slowdown on that road. This information is valuable to local authorities (to alert them to a traffic accident, for instance) and also very valuable to other motorists (or boaters), who could receive this information on their GPS unit or through another source such as a traffic radio station.